Composite multiple and incrementally controlled steam chamber for applying dried steam to a pulp mat

ABSTRACT

A composite steam chamber extending transversely above a pulp mat for discharging steam down onto the mat; the composite chamber formed of separate individual chambers secured together including one or more central or inner chambers and an end chamber at each end of the composite structure; means for separately delivering steam into each individual chamber; each individual chamber having a bottom wall formed into ridges and valleys extending from one end wall of the chamber to the other, with steam jet orifices in the ridges; and means for drawing off moisture collecting in the valleys of each individual chamber.

April 10, 1973 J. H. DUPASQUIER COMPOSITE MULTIPLE AND INCREMENTALLYCONTROLLED STEAM CHAMBER FOR APPLYING DRIED STEAM TO A PULP MAT FiledJune 28, 1971 2 Sheets-Sheet 1 FIG.

R Em T QN E MV m D H H P E S O J ATTY.

Apnl 10, 1973 .1. H. DUPASQUIER 3,726,757

COMPOSITE MULTIPLE AND INCREMENTALLY CONTROLLED STEAM CHAMBER FORAPPLYING DRIED STEAM TO A PULP MAT Filed June 28, 1971 2 Sheets-Sheet 2b I? FIG. 4

l6 3 ;Z l II 53 I JOSEPH H. DUPASQUIER 1; INVENTOR.

United States PatentO COMPOSITE MULTIPLE AND INCREMENTALLY CONTROLLEDSTEAM CHAMBER FOR APPLY- ING DRIED STEAM TO A PULP MAT Joseph H.Dupasquier, 5855 NW. Skyline Drive, West Linn, Oreg. 97068 Filed June28, 1971, Ser. No. 157,175 Int. Cl. D21f /18 US. Cl. 162-290 1 ClaimABSTRACT OF THE DISCLOSURE A composite steam chamber extendingtransversely above a pulp mat for discharging steam down onto the mat;the composite chamber formed of separate individual chambers securedtogether including one or more central or inner chambers and an endchamber at each end of the composite structure; means for separatelydelivering steam into each individual chamber; each individual chamberhaving a bottom wall formed into ridges and valleys extending from oneend wall of the chamber to the other, with steam jet orifices in theridges; and means for drawing off moisture collecting in the valleys ofeach individual chamber.

BACKGROUND OF THE INVENTION US. 'Pat. No. 2,838,982, issued June 17,1958, describes an apparatus for applying dried steam down onto atraveling pulp mat in order to aid in the evaporating of water from thepulp mat. The device of the present invention is very similar to that ofthis earlier patent. However, particularly when a pulp mat is ofconsiderable width, with the Well-known tendency of the edge portions ofthe traveling pulp mat to lose moisture more rapidly than the centerportion, it is most desirable to be able to control the application ofthe steam to the mat proportionately across the respective areas of themat instead of applying the steam equally over the entire mat asprovided in the device of 'Pat. No. 2,838,982. Accordingly, the objectof the present invention is to provide an apparatus for discharging drysteam down onto the mat, which apparatus will be composed of separatesteam chambers, each separately and independently controlled, and soarranged that a desired proportionately greater amount of steam can beapplied to the center portions of the mat than to the edge portions.

SUMMARY OF THE INVENTION The device is formed of a plurality ofindividual steam chambers, secured end-to-end so as to form a compositedevice extending transversely over the entire pulp mat passing beneaththe device. The individual steam chambers are similar, being of the samewidth and transverse cross-section, with each chamber having a bottomwall formed into ridges and valleys, similar to the bottom wall in thedevice of the above mentioned US. Pat. No. 2,838,982, and thus with thesteam from each chamber being discharged from orifices in the ridges inthe bottom wall while the moisture from the steam in each chamber iscollected in the valleys between the ridges. Means are provided fordraining ofi the moisture collected in the valleys of the chambersseparately, and the delivery of steam into the separate chambers is alsoseparately controlled. The end chambers of the composite device are soarranged that the desired proportionately less steam can be dischargeddown on the edge portions of the pulp mat and a greater amount of steamdischarged down on the center portion of the mat where most needed.

3,726,757 Patented Apr. 10, 1973 BRIEF DESCRIPTION OF THE DRAWINGS Inthe drawings:

FIG. 1 is a foreshortened top plan view of a compos te steam chamberbuilt in accordance with the present 1nvention, comprising an innerchamber and two end chambers, the composite device extendingtransversely above a traveling pulp mat;

FIG. 2 is a fragmentary sectional elevation taken on line 2--2 of 'FIG.1, drawn to a considerably enlarged scale;

FIG. 3 is a foreshortened top plan view, similar in part to FIG. 1, ofone of the end chambers of the composite device, but illustrating inpart a modified construction of the device;

FIG. 4 is a fragmentary sectional elevation on line 4-4 of FIG. 3, drawnto the same scale as FIG. 2, with a portion of the transverse trough inthe end of the inner chamber broken away for clarity;

FIG. 5 is a fragmentary and foreshortened longitudinal sectionalelevation taken on line 55 of FIG. 3 and FIG. 4, drawn to the same scaleas FIG. 4, with portions broken away for clarity;

FIG. '6 is a fragmentary section of FIG. 4; and

FIG. 7 is a fragmentary section taken on line 7-7 of FIG. 6.

Referring first to FIG. 1, the composite steam-applying apparatus asillustrated consists of three separate closed chambers, namely an innerchamber 10 and two end chambers 11 and 12, the end chambers secured tothe ends of the inner chamber 10 respectively. All three chambers areidentical in cross-sectional shape and size and together form astationary composite apparatus extending entirely across the travelingpulp mat P, the apparatus being supported by suitable means (not shown)with the bottom of the apparatus spaced slightly above the pulp mat,which mat is carried along the Fourdrrnier wire F of the paper-makingmachine in the customary manner.

The bottom wall of each of the chambers 10, 11 and 12, like the bottomwall of the steam-applying device of the above mentioned US. Pat. No.2,838,982, is formed into a series of V-shaped sections formingalternate ridges 13 and valleys 14 (see FIG. 2) extending from one endof each chamber to the other, the ridges lying in a substantiallyhorizontal plane parallel to the Fourdrinier wire and the valleys 14similarly lying in a horizontal plane except that the valley 14' at eachside of each chamber is located below the level of the other valleys andextends to the plane of the bottom edge of the longitudinal side walland the bottom edges of the end walls of the entire device. The ridgesand valleys of all the chambers 10, 11 and 12 preferably are inalignment respectively. The end chambers 11 and 12 are secured to theinner chamber 10, preferably by having their inner end walls omitted andbeing welded instead to the respective end walls 15 and 16 of the innerchamber 10.

Along each of the top ridges 13 of the bottom walls of the threechambers a plurality of spaced orifices 17 are provided through whichsteam jets are directed down onto the pulp mat. In the two end chambers11 and 12 the valleys 14 have drain outlets in the outer end walls whichare controlled by drain taps 18 (FIG. 1) on the outside of the endwalls, and similarly the lower valleys 14' in these two chambers aredrained through drain taps 19.

In the form of the device shown in FIGS. 1 and 2, the valleys 14 of thebottom wall of the inner chamber 10 are drained by a central transversecut-away pipe or trough 20 which intercepts the valleys. The ends ofthis taken on line 6-6 cross pipe 20 terminate in and discharge into thelower valleys 14' on the opposite sides of the chamber respectively, oneof these ends being shown in FIG. 2. A cleanout plug 22 (one of which isshown more clearly in FIG. 2) is provided in each of the sides of thechamber wall in axial alignment with the corresponding end of pipe 20 asa convenience in aiding in the cleaning of the pipe 20 if for any reasonthis should becomes necessary. A sealed and locked inspection plate 23and vacuum breaker (FIG. 1) is located in the upper side wall of thechamber 10. In order to drain off the water collected in the lowervalleys 14' along each side of the inner chamer 10 and any waterdischarged into these valleys from the cross pipe 20, and therewith fromthe valleys 14 of the inner chamber 10, an outlet 24 is provided at thebottom of each side wall of the chamber 10 in the locatron shown inFIGS. 1 and 2. Each of these outlets is connected to a pipe 25 whichextends longitudinally along on the outside of the chamber and continuesalong the outside of an end chamber (in this case end chamber 11, asshown in FIG. 1), to an outer end of the device, these pipes beingsupported by suitable brackets 26. A drain tap 27 is located at the endof each of these outside pipes.

Steam under pressure from a suitable source (not shown) is delivered bya pipe 10 through an inlet 29 (FIG. 1) preferably at the center of thetop of the chamber 10 and is discharged throughout the interior ofchamber 10, preferably through the intermediary of a pair ofoppositely-directed nozzles in the chamber (indicated by the brokenlines 30 in FIG. 1). Also steam from the suitable source is deliveredinto the chambers 11 and 12 through the pipes 11' and 12'. Suitablecontrols (not shown) are provided on each of the pipes 10', 11 and 12'.

Preferably, but not necessarily, a small orifice 31 (FIG. 2) extendsthrough each end wall of chamber 10 at the termination of each valley 14to allow some moisture at that end of the valley and a small amount ofsteam to be discharged into the adjacent chamber. The chamber 10 isprovided with a safety blowout disc 32 to serve in the event that steampressure in chamber 10 should for any reason build up in excess of thedesired safety range. A pressure gauge (not shown) is also mounted oneach of the chambers 10, 11 and 12. The end chambers 11 and 12 are alsosimilarly provided with inspection plates and blowout discs (not shown).

Thus the dried steam, discharged down on the pulp mat passing alongbeneath the device or composite steam chamber, may be deliveredproportionately on the pulp mat as desired with the greater amountdelivered on the central portion of the mat where it is most needed, andwith predetermined lesser amounts delivered down onto the edge portionsas circumstances may require in order to aid in causing more uniformdrying of the traveling mat across its entire width.

While the device is described as composed of a single inner chamber andtwo end chambers, it would be possible to have two inner chambers,joined end-to-end, with the two end chambers connected respectively tothe outer ends of these two inner chambers. However, for all practicalpurposes, even for wide pulp mats, it has been found sufficient andsatisfactory to have a single inner chamber and two end chambers,substantially as shown, with the length of the device made according tothe particular papermaking machine and width of the pulp mat on whichthe device is to be used, and with the individual chambers made ofvarious lengths as required. Also, it would be possible to have theinner end walls left on the end chambers 11 and 12 and to have theextending flanges of these walls bolted to the extending flanges of theend walls of the inner chamber 10, with suitable sealing gasketstherebetween, instead of having the end chambers welded to the end wallsof the inner chamber 10. However, it is considered preferable and morepractical to have the end chambers welded to the end walls of the innerchamber as described since ordinarily the device will be manufactured 4specifically to suit a particular paper-making machine, and forpermanent mounting thereon.

FIGS. 3 to 7 inclusive illustrate a modification in the construction ofthe device in which a transversely-extending trough at one end of theinner chamber 10 is used for disposing of the water collecting in thevalleys 14 at the bottom of that chamber, in place of the cross pipe 20previously described with reference to FIGS. 1 and 2. This transverseend trough (shown best in FIGS. 4 and 5) is formed by the end wall 16 ofthe chamber 10 and a downwardly sloping baffle wall 33 which slopesdownwardly toward the end wall 16 and at the bottom is joined to thebottom of the end Wall 16. The top edge of this trough wall 33 conformsto the ridges 13 and valleys 14 forming the bottom of the chamber 10.

A drain opening 34 (FIGS. 4 and 5) in each of the valleys 14 of thechamber 10 is located near the end wall 16 of the chamber within thetrough wall 33 so that any water collecting in the valleys 14 in thechamber 10 will pass down into the bottom of the trough thus formed.

In this modified form the end wall 16 of the chamber 10 is provided witha bottom aperture 35 at the end of each of the two lower side valleys14', one of these apertures 35 being shown in FIGS. 4, 5 and 6. A pairof drain pipes 36, one of which is shown in the drawings, extendingrespectively along the corresponding lower side valleys 14 in the endchamber 12, have their inner ends extending through the correspondingbottom aperture 35 in the wall 16 of the chamber 10, and, as apparentfrom FIG. 6, carry off the water collected in the transverse trough atthe end wall 16 of the chamber and in the lower side valleys 14' of thechamber 10. Each of these pipes 36 extends out through an apertureformed in the outer end wall 37 of the end chamber 12 and is controlledby a suitable drain tap 38. Thus, with this modified construction, allthe water collected from the steam in the inner chamber 10 can be drawnolf through the two pipes 36 which extend through the end chamber 12 andit is not necessary to have any external drain pipe for the innerchamber 10.

As previously mentioned, each of the valleys 14 of the end chambers 11and 12 is drained through a drain tap 18 on the outer end wall. In orderto provide for drainage of the lower bottom side valleys 14 in the endchamber 12 with this modified construction, without interfering with thedrain pipes 36 from the inner chamber, an inside opening 39 near theouter end of each of the side valleys 14' for the end chamber 12 leadsinto a small, closed compartment 40 which in turn discharges through anaperture 41 in the outer end wall 37 of the chamber 12 and is controlledby a drain tap 42, as shown in FIGS. 7 and 3. Only one of these enddrainage compartments 40 is shown in the figures, but it is to beunderstood that the drainage compartment for the other lower side valley14' for the chamber 12 is similarly arranged.

It will be possible, as previously mentioned, to have the devicecomposed of two inner chambers, joined endto-end with two end chambersconnected to the respective outer ends of the two inner chambers. Insuch case, with the employment of the modified drainage means, each ofthe inner chambers would have a transverse drainage trough at its outerend which would discharge through a pair of pipes located in the lowerside valleys 14 of the adjacent end chamber. However, also as previouslyindicated, the forming of the composite steam chamber with a singleinner chamber and a pair of independently controlled end chambers isconsidered adequate for any paper-making machine of present use.

In either case the incremental design and construction of the devicemakes it possible to apply the steam proportionately as needed andthereby constitutes a moisture profile control.

I claim:

1. In a paper-making machine in which a pulp mat is carried along on aFourdrinier wire, a device positioned above the Fourdrinier wire andextending transversely J from one side of the wire to the other fordischarging relatively dry steam down onto the pulp mat, said devicecomprising a plurality of separate steam chambers with means fordelivering steam under desired pressures separately into each chamber,said chambers being of the same width and secured end-to-end, the bottomwalls of said chambers being formed into a series of ridges and valleysextending from one end of each chamber to the other, said ridges andsaid valleys extending in planes parallel to said Fourdrinier wire, theridges and valleys of said bottom walls of said chambers being inalignment respectively, the valleys at the side walls of said chamberslying in a plane slightly lower than the plane of the other valleys,each of said ridges in said bottom walls of said chambers having a rowof steam jet openings dis charging downwardly onto said pulp mat, saidchambers at the two ends of said device being similar, drains for saidvalleys in said bottom walls of said two end chambers mounted in therespective outer end walls of said end chambers, an inner chamber insaid device located inwardly of an end chamber, a transversely-extendingtrough in the end of said inner chamber, said trough formed by adownward, obliquely-sloping wall joining the bottom edge of an end wallof said inner chamber, the top edge of said downward, obliquely-slopingwall conforming to the ridges and valleys in the bottom of said innercham- 6 her, said valleys in said inner chamber, With the exception ofthe two lower valleys at the sides of said inner chamber, havingdischarge outlets opening into said trough, means defining a pair ofoutlet apertures in said end wall of said inner chamber at the ends ofthe lower side valleys respectively of said inner chamber, and a pair ofdrain pipes extending along in the side valleys of an adjacent endchamber and leading from said outlet apertures respectively, the outerends of said drain pipes extending through the outer end wall of saidlatter mentioned end chamber, and a drain tap at the outer end of eachof said drain pipes.

References Cited UNITED STATES PATENTS 3,669,831 6/1972 Dupasquier162-290 2,838,982 6/ 1958 Dupasquier 162-290 X 153,139 7/1874 Wilmot165-110 3,097,994 7/ 1963 Dickens et al 162-308 X S. LEON BASHORE,Primary Examiner R. V. FISHER, Assistant Examiner US. Cl. X.-R.

